Changeset 6e49c3474539a6c60ade3911897032696b324db7 for oggzcap/src/videoout/encoder_example.c

Timestamp:

02/21/10 23:59:26 (2 years ago)

Author:

Robin Gareus <rgareus@…>

Parents:

66e0a72e52b6c9076ab19cebe52ae0ada6898d4a

Children:

26852f5d3ef287c9672aba17dc5f0bfa3f9a2396

git-committer:

Robin Gareus <rgareus@priroda.local> / 2010-02-22T00:59:26Z+0100

Message:

better RGB -> YUV convertion

Files:

• oggzcap/src/videoout/encoder_example.c (modified) (2 diffs)

oggzcap/src/videoout/encoder_example.c

@@ -86 +86 @@
         cr_base += dst->uv_stride;
     }
-#else // RGBA -> 420
+#else // RGBA -> 420 
+        // TODO: offset ! & strides
         
 #define _CR ((bptr[(4*i)+2])&0xff)
@@ -92 +93 @@
 #define _CB ((bptr[(4*i)+0])&0xff)
         
+#define _CRX ( ( ((bptr[(4*i)+2])&0xff) + ((bptr[(4*(i+1))+2])&0xff) + ((bptr[(4*(i+1+width))+2])&0xff) + ((bptr[(4*(i+1+width))+2])&0xff) )>>2)
+#define _CGX ( ( ((bptr[(4*i)+1])&0xff) + ((bptr[(4*(i+1))+1])&0xff) + ((bptr[(4*(i+1+width))+1])&0xff) + ((bptr[(4*(i+1+width))+1])&0xff) )>>2)
+#define _CBX ( ( ((bptr[(4*i)+0])&0xff) + ((bptr[(4*(i+1))+0])&0xff) + ((bptr[(4*(i+1+width))+0])&0xff) + ((bptr[(4*(i+1+width))+0])&0xff) )>>2)
+        
         uint8_t *bptr = (uint8_t*) b_2vuy;
         int i; int c=0;
         for (i=0;i<width*height;i++) {
-                double Y  = (0.257 * _CR) + (0.504 * _CG) + (0.098 * _CB) + 16;
+                double Y  = (0.299 * _CR) + (0.587 * _CG) + (0.114 * _CB);
                 if (Y<0) dst->y[i]=0;
                 else if (Y>255) dst->y[i]=255;
                 else dst->y[i]=(uint8_t) floor(Y+.5);
 #if 1
-                if (i%2==0 && ((i/width)%2)==0) { // TODO average 4 pixels
-            double V =  (0.439 * _CR) - (0.368 * _CG) - (0.071 * _CB) + 128;
-            double U = -(0.148 * _CR) - (0.291 * _CG) + (0.439 * _CB) + 128;
+                if (i%2==0 && ((i/width)%2)==0) { 
+            double V =  (0.500 * _CRX) - (0.419 * _CGX) - (0.081 * _CBX) + 128;
+            double U = -(0.169 * _CRX) - (0.331 * _CGX) + (0.500 * _CBX) + 128;
                         
             if (U<0) dst->u[c]=0;